Dodge City times. [volume] (Dodge City, Kan.) 1876-1892, 1887-11-10
Facts About Lightning.

Every one is familiar with the fact
that lightning does not spring from
cloud to cloud, to the earth, but pursues
zig. gag course. This is due to the
fact that the air is not equally humid
throughout. Electricity always takes
the path which offers the least resist
ance toits passage. Damp air is bet
ter conducting medium than dry AIR;
consequently the lightning selects the
dampest route, avoiding the dryer strata
and zones 1t encounters, and advances
now directly, now obliquely, until it
reaches the opposite cloud, where it SUBJ
divides into number of forks. Owing
to the resistance it encounters in its
path intense heat is generated, which
causes the air to expand. Immediately
after the flash, the air again contracts
with great violence and with loud re-
port which is echoed and re-echoed
among the clouds. The report reaching
the ear of the listener from varying dis
tances, is drawn out into series, and,
being still further prolonged by the
echoes, the roll Of the thunder is pro-
duced.
1t is curious fact that, although the
sound of thunder is exceedingly loud
when heard near at hand, the area over
which it is audible is comparatively
circumscribed. The noise of can
nonade will be heard, under favorable
conditions, at distance of nearly a
hundred miles, while the sound of thun-
der does not travel over fifteen miles.
The occurrence of the thunder and the
lightning is Of course, simultaneous,
but as the light travels faster than
sound-its passage is almost instanta-
neous, the fash may be seen several Sec
onds before the thunder is heard. The
distance of thunder may thus be ap-
proximately estimated, an interval of
five seconds between the fash and the
thunder clap being allowed to the mile.
Sheet-lightning has the appearance
of sheet Of fame, momentariIy illu-
minating part of the sky or cloud sur
face. 1t is, in reality, but the reflect
ion Of lightning flashing beyond the
horizon or behind the clouds, at too
great distance for the thunder to be
audible.
But the most remarkable of all the
manifestations Of electricity is globular
lightning, in appearance like ball Of
fire moving leisurely along, and remain
ing visible, it may be-, several minutes.
Many curious facts are related Of its
vagaries. One of the most interesting
and circumstantial is that given by Mr..
Fitzgerald, County Donegal, Ireland,
who saw globe of fire slowly descend
from the Glendowan mountains to the
valleys below. Where it first touched
the ground, it excavated hole about
twenty feet square, las if it had been
cut with a huge knife
This was scarcely the work of a min
ute. For distance of twenty perches
it plowed trench about four feet deep
and moving along the bank of stream
it made furrow foot in depth. Fin
ally it tore away part Of the bank five
perches in length, and five feet deep,
and hurting the immense mass into the
bed of the stream it flew into the OPP
posite peaty bank. The globe was visi
bic twenty minutes, and traversed a
distance Of a mile, showing that its pro-
gress was, for lightning, very slow in
deed. During thunder storms of ex-
treme violence on Deeside, balls of fire
are occasionally seen to roll down the
sides of Lochnagar, which are, no doubt
identical with globular lightning
Chamber Journal.